>So this is a DE class that you created and have in a VCX that you have defined for use by this form?

er... no. Standard form and DE

>>If so, is there any code in your DE class? I am not aware of ANY code that would be visible in the debugger for events being fired internally by VFP. So any code you are seeing should be developer code from somewhere.

hmmm... I take your point. Even weirder than I supposed. And that inspired me to go into the DE, and insert the code (in the init of the relevant cursor)

NODEFAULT
SET ORDER TO (blah) in (relevant table)

and now it runs sweet as a nut.

Problem, of course, is that this shouldn't be necessary!